As we are preparing the Dune 2.0.0 release, we wanted to share a few words about it. Most of it is straightforward. One notable change is that Dune 2 will require a recent version of OCaml to build itself, however it will still be able to build projects using older compilers and will still be installable in older opam switches. We will also provide one additional year of support for Dune 1.
Update: after thinking about this more and working more towards preparing Dune 2.0.0, we made the following changes compared to this post:
- The source code of Dune itself will remain compatible with the last 3 released versions of OCaml rather than just the last one. i.e. if 4.08 is the last released version of OCaml when Dune 2.0.0 is released then Dune 2.0.0 will be guaranteed to build with OCaml 4.06, 4.07 and 4.08. We still plan to provide an easy way to install Dune 2.0.0 in older opam switches
- Dune 2.0.0 will not be able to read jbuild files at all. Only
dune upgrade will still be able to read them in order to upgrade them